Self-Uniting companion .ini

Advanced reference

Reference for developers and system administrators.

When a split includes the Self-Uniting app, GSplit writes a text file next to the copy of GUnite.exe: the app and its .ini share a name (GUnite.exe and GUnite.ini, Restore.exe and Restore.ini). The app, started without a piece, reads this file and restores the set it describes. The file carries a version number, format=1.

You can read it, check it, or write your own: any program that produces this format can drive GUnite.exe. The pieces themselves are described in Piece format V4.

File format

Encoding: UTF-8, without a byte order mark.
One key=value per line, in [section] blocks. Values are not quoted.
A multi-line or special value is stored on one line, with these escapes:

Sequence	Meaning
`\n`	Line break
`\\`	Backslash
`\s`	A space at the start or end of the value (the reader trims values)
`\xHH`	Any other control character, in hexadecimal

Booleans are 0 or 1. Absent, or anything else, means the default.
Text values that GSplit writes escaped are marked escaped in the tables below.

Example

[gunite]
format=1
program=GUnite.exe

[set]
id={4f2c8a10-5b3e-4d6a-9c1f-0a7e2b9d3c55}
label=
title=Holiday video
author=Anna
description=Summer 2026
created=2026-10-21 19:30:05

[source]
name=film.bin
size=52428800
sha256=9f86d081884c7d659a2feaa0c55ad015a3bf4f1b2b0b822cd15d6c15b0f00a08
pieceCount=6
pieceMask=disk{num}.gsd
firstPiece=disk1.gsd

[options]
welcome=Welcome to this app. It will restore the following file:\n\n film.bin\n ...
messageAtStart=
messageAtEnd=
about=This file was split with GSplit freely available at www.gdgsoft.com
destination=3
customFolder=
lockDestination=0
askOverwrite=1
openAfter=0
waitForEnd=0
deleteAfterRun=0
openParams=
autoClose=0
autoStart=0
silent=0
headerImage=
languageFile=

[pieces]
1=disk1.gsd|10485760|89ABCDEF
2=disk2.gsd|10485760|01234567

Section [gunite]

Key	Type	Default	Meaning
`format`	integer	`1`	Version of the format.
`program`	text	empty	File name of the app that was written.

Section [set]

Key	Type	Default	Meaning
`id`	text, escaped	empty	The set identifier: the canonical UUID, in braces, that every V4 piece carries.
`label`	text, escaped	empty	The identifier text you typed when it was not a UUID; empty otherwise.
`title`	text, escaped	empty	Title of the set.
`author`	text, escaped	empty	Author.
`description`	text, escaped	empty	Description.
`created`	date and time	none	Date of the split in local time, `yyyy-mm-dd hh:nn:ss` (19 characters). Any other length is ignored.

Section [source]

This section is required, with [pieces]; without either, the app refuses the file.

Key	Type	Default	Meaning
`name`	text, escaped	`united`	File name of the original, which is also the name of the restored file.
`size`	integer	`-1`	Size of the original in bytes.
`sha256`	text	empty	SHA-256 of the original, 64 hexadecimal digits. Informative.
`pieceCount`	integer	`0`	Number of pieces. `0` means the number of lines in `[pieces]`.
`pieceMask`	text, escaped	empty	The naming mask of the pieces, for example `disk{num}.gsd`.
`firstPiece`	text, escaped	empty	File name of piece 1. Written for readers; the app takes piece 1 from `[pieces]`.

Section [options]

These keys come from the Operation page.

Key	Type	Default	Meaning
`welcome`	text, escaped	empty	Welcome message. GSplit has already replaced the placeholders (`{filename}`, `{desc}`, `{size}`, `{fullsize}`, `{piececount}`, `{author}`).
`messageAtStart`	text, escaped	empty	Message shown at the start.
`messageAtEnd`	text, escaped	empty	Message shown after a successful run.
`about`	text, escaped	empty	About message.
`destination`	integer	`3`	Destination folder: `0` Windows folder, `1` System folder, `2` Temp folder, `3` current folder, `4` folder of the app, `5` custom folder. A value outside 0 to 5 gives `3`.
`customFolder`	text, escaped	empty	Folder used with `destination=5`.
`lockDestination`	boolean	`0`	The user cannot change the destination folder.
`askOverwrite`	boolean	`1`	Ask before replacing an existing output file.
`openAfter`	boolean	`0`	Open the restored file (Windows).
`waitForEnd`	boolean	`0`	Wait for the program that opened the file.
`deleteAfterRun`	boolean	`0`	Delete the restored file afterwards. Needs `waitForEnd`.
`openParams`	text, escaped	empty	Parameters passed to the program that opens the file.
`autoClose`	boolean	`0`	Close the app after a successful run.
`autoStart`	boolean	`0`	Start without waiting for the user.
`silent`	boolean	`0`	No window, no questions.
`headerImage`	text, escaped	empty	File name of the header image, next to the app.
`languageFile`	text, escaped	empty	File name of the `.po` catalog, next to the `.ini`.

On Linux, destination values 0 and 1 mean the current folder, and openAfter, waitForEnd and deleteAfterRun are ignored.

Section [pieces]

One line per piece, sorted by number:

number=name|size|crc32

Part	Type	Meaning
`number`	integer, 1 or more	Position of the piece in the set.
`name`	text, escaped	File name of the piece, without a folder.
`size`	integer	Size of the piece file in bytes. `-1` if the value cannot be read.
`crc32`	hexadecimal	Standard CRC-32 of the piece file, 8 digits (`0` if the value cannot be read).

At least one valid line is required. A line without both | separators, with a number below 1 or with an empty name makes the file invalid.

Names from the file are not trusted

The .ini travels with the pieces, so the app does not trust the names in it. For name and for each piece name, only the part after the last / or \ is kept. On Windows, characters the file system refuses become _ and trailing dots and spaces are removed. An empty name, ., .., a control character or a Windows device name (CON, NUL, COM1…) gives united for the source and an invalid line for a piece. Every change is shown to the user before the run.